Reductive Ring Opening of Oxygen-Containing Benzo-Fused Heterocycles by an Arene-Catalysed Lithiation
作者:Miguel Yus、Benjamín Moreno、Francisco Foubelo
DOI:10.1055/s-2004-815971
日期:——
The reductive ring opening of phthalan and isochroman in a 8 mmol scale process, using a small excess of lithium (1.35 equiv) and a substoichiometric amount of DTBB (3 mol%), leads to functionalised organolithium compounds, which after reaction with (-)-menthone as electrophile followed by hydrolysis with water, gives the corresponding diols in good yields with high stereoselectivity. Dehydration of these diols leads to the corresponding oxygen-containing heterocycles, which are homologous of the starting heterocycles.
使用过量的锂(1.35当量)和次化学计量的二叔丁基二硫(3摩尔%),在8毫摩尔规模下进行酞喃和异色满的还原开环反应,得到功能化的有机锂化合物。通过与(-)-薄荷酮作为亲电试剂反应,然后用水进行水解,可以高产率、高立体选择性地获得相应的二醇。这些二醇的脱水反应生成含氧杂环,它们是起始杂环的同系物。